Do Catholics believe in the Old Testament?

[hnjames]

I have a sister-in-law who was a catholic but is now a Baptist who is completely anti-catholic. She claims that Catholics do not believe in the Old Testament and it’s prophecies and the Holy Spirit. She calls the catholic religion a ‘cult’. Please suggest a book or article that I can verify and be able to give her a clear cut answer. She refuses to read any catholic books. She so much thinks that we will all go to hell. I feel sorry for her and want show her how wrong she is about the catholic faith.
Thanks

PS: not sure what the tags are for below!

 

[Augusta_Crowley]

The following links should help answer your question about the Old Testament. If you have any further questions, please contact Catholic Answers directly.

Recommended Reading:

How important is the Old Testament?
What Do Catholics Think of the Bible?